Features: 1. USB Powered: With the USB interface design, the heated gloves hand warmers bag can be powered via your PC, power bank, or car charger, and can work for up to multiple hours after fully charged. 2. Keep Your Feet Warm: Heated socks can keep feet comfortable and warm in cold weather or extreme operating temperatures. One size for most people. 3. Soft And Breathable: Electric Thermal Socks are made of premium cotton, soft, breathable, and elastic, which is skin-friendly, keeping your feet warm and cozy. Better than wool socks, doesn't itch like wool, and is warmer. 4. Safety To Use: The heating elements of the battery-heated socks are made of insulating material, no worries about heating safety. Comfortable heating temperature lets your feet no longer be cold and stiff in the cold winter. 5. Necessary for Winter: With the electric heating socks, you can enjoy your fishing, camping, snowboarding, hunting, hiking, skiing, snowboarding, outdoor work, etc. The winter foot warmer socks are a considerate gift for your parents, friends, and family. Specification: Material: Cotton Product Color: Gray, Black Product Size: 80 x 49 x 13mm Product Weight: 500g 3-Speed Temperature: 45, 45, 50C Voltage: 3.7v Battery: 4000nAh Package Included: 1 Pair x Heated Socks Have a great time shopping!